Aka pulse-temperature disassociation (it is French, so pronounced fah-jay. Warning: using a hard g will result in suffering the approbation of others). Liebermeister's rule: When the temperature goes up a degree, the pulse should go up 10 (except, of course, when the patient has heart block from their myocardial abscess or is on beta-blockers). So when the febrile patients does not get appropriately tachycardic, they have [[Faget's Sign]]. It has an interesting differential that is always fun for Chief of Service rounds: *[[Salmonella]]* *typhii*, [[Brucella]], *[[Chlamydia]]* *psittaci*, [[Legionella]], *[[Francisella]]* *tularensis*, [[Yellow Fever]] (for which it was first observed), [[Dengue]] are the big ones. Also [[Colorado Tick Fever]], *[[Mycoplasma]]* *[[pneumonia]]*, and [[COVID]] 45.